according to heisenbergs uncertainty principle

Question

According to Heisenberg's uncertainty principle, the product of uncertainties in position and velocities for an electron of mass 9.1x 10 ^-31 kg is:

(1) 2.8x 10 ^-3 m²-s^-1                      

(2)  3.8x 10^-5 m² s^-1        

(3)  5.8x 10^-5 m²s^-1                       

(4) 6.8 x 10 ^-6 m²  s^-1

Ans:   5.8x 10^-5 m²s^-1